// Copyright 2017 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef V8_OBJECTS_DATA_HANDLER_H_
#define V8_OBJECTS_DATA_HANDLER_H_

#include "src/objects/struct.h"

// Has to be the last include (doesn't have include guards):
#include "src/objects/object-macros.h"

namespace v8 {
namespace internal {

    // DataHandler is a base class for load and store handlers that can't be
    // encoded in one Smi. Kind of a handler can be deduced from instance type.
    class DataHandler : public Struct {
    public:
        // [smi_handler]: A Smi which encodes a handler or Code object (we still
        // use code handlers for accessing lexical environment variables, but soon
        // only smi handlers will remain). See LoadHandler and StoreHandler for
        // details about encoding.
        DECL_ACCESSORS(smi_handler, Object)

        // [validity_cell]: A validity Cell that guards prototype chain modifications.
        DECL_ACCESSORS(validity_cell, Object)

        // Returns number of optional data fields available in the object.
        inline int data_field_count() const;

        // [data1-3]: These are optional general-purpose fields whose content and
        // presence depends on the handler kind.
        DECL_ACCESSORS(data1, MaybeObject)
        DECL_ACCESSORS(data2, MaybeObject)
        DECL_ACCESSORS(data3, MaybeObject)

        DEFINE_FIELD_OFFSET_CONSTANTS(HeapObject::kHeaderSize,
            TORQUE_GENERATED_DATA_HANDLER_FIELDS)

        static const int kSizeWithData0 = kData1Offset;
        static const int kSizeWithData1 = kData2Offset;
        static const int kSizeWithData2 = kData3Offset;
        static const int kSizeWithData3 = kSize;

        DECL_CAST(DataHandler)

        DECL_VERIFIER(DataHandler)

        class BodyDescriptor;

        OBJECT_CONSTRUCTORS(DataHandler, Struct);
    };

} // namespace internal
} // namespace v8

#include "src/objects/object-macros-undef.h"

#endif // V8_OBJECTS_DATA_HANDLER_H_
